Electric-lamp socket.



a SHEETS-SHEET 1.

B. BENJAMIN.

`ELEGTRIG LAMP SOCKET.

11.1.1511 JULY18,1910. RENEWBD SEPT. 18, 1913.

` Patented Mar. 3, 1914.

W im@ R. B. BENJAMIN.

ELECTRIC LAMP SOCKET.

APPLICATION HLED JULY1s,191o. RBNBWBD SEPT.111,1913.

17,088,867"o Patented Mar. 3, 1914.

3 SHEETS-SHEET 2.

my I mmfo@ Mm R E, BENJAMN. ELECTRIC LAMP BUCKET ArPLIoATIoN Hmm JULY 1s, w10. RBNBWED SEPT. 1s, 191s.

Patented Mar. 3, 1591i 3 SHEETS-SHEET 3.

Unirnn srarns PATENT OFFICE.

REUBEN B. BENJAMIN, F CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, T0 GENERAL ELECTRIC COMPANY, OF SCHENECTADY, NEW YORK, A CORPORATION 0F NEW YORK.

Specification of Letters Patent.

Application illed July 18, 1910, Serial No. 572,503. Renewed September 18, 1913. Serial No. 790,565.

To all whom it may concern:

Be it'known that I, ^REUBEN B. BENaA- MIN, a citizen of the United States, resid- -ing at Chicago, in the county of Cook and ence being had to the accompanying drawing, forming a part of this s'peciication.

My invention pertains to high tension series lamp sockets and particularly to sockets which are provided with means whereby the lamp contacts are short-circuited in caseI of the destruction of the lamp.

It is one o-f the objects of my invention to improve upon sockets of this character.

In order that my invention may be clearly `understood,-I have described one embodiment thereof in the following specification,

- reference being had to the accompanying drawings,l in which:

Figure lis an inverted plan of the body of the socket, the separable lamp receiver being removed; Fig. 2 is a fragmentary section taken on the line 2-2 of Fig. 1, the lamp receiver being shown connected to the body; Fig. 3 is a Vertical section taken on the line 3-3 of Fig. 1, the lamp receiver being shown connected to the body; Fig. 4 is a vertical section taken on the line 4-#4 of Fig. 1; Fig. 5 is a plan ofthe lamp re.

ceiveralone; Figs. 6 and 7 are side elevations of the lamp receiver looking in the direction of the arrows 6-.6 and 7 -7, respectively on Fig. 5; Fig. 8 is a view similar to Fig. 6 but showing the parts of the lamp receiver in a different position; Fig, 9 is a detail view of the locking catch for securing the lamp receiver against accidental separation from the body; and Fig. 1() is a fragmentary section taken onV the line 10-10 of Fig. 6. v .v

The socket is made in two separable portions, one of which (herein termed the body.) is adapted to be attached to a suit- Sablesupporti-n device, such as a conduit or the like, T e body carries the binding terminals and the centerl lamp engaging contact. The other portion (herein called the lamp receiver carries the threaded lamp receiving shell, which, when the ortions are connected together, is brought into electrical connection wit-h one of the binding terminals. One of these ortions carries a pair of contacts which, w' en connected, short-circuit the lamp engaging contacts, and between which may be placed a lm of mica, or other insulating material, of suoli thickness that it can be 'broken down by the current. when the latter can find no shunt path throughthe lamp. By this means the socket is short-circuited in case of the destruction of the lamp carried thereby and the extinguishingof the other lamps c0nnected in the circuit is avoided Referring now to the drawings by reference characters, the body consists of a base 11 which is formed with two lateral extensions or knobs 12 around which the conductors may be passed in order to lead them to the bind-ing terminals. Secured to the base 11 by means of screws 13 is a supporting member 14', the upper end of which is threaded to receive a bushing 15 which is internally screw threadedV to receive a conduit or other support 16. Surrounding disk 20, and the depth of the insulating` hood 19, being such that the lower edge of the hood presses firmly upon the rubber disk, whereby a watertight connection is formed y The base 11 is hollowed out at its lower side to form a chamber 21 in which the various conducting parts -of the socket are mounted. In a recess in the bottom of this chamber is secured, by means of screws 22,

jacent one end of a groove 25 formed in the lower face of the base directly beneath one of the knobs l2. This groove provides a passage way for th'e lead conductor which is to be connected to the binding terminal 24. Clamped beneath the plate 23 is an arched resilient member which forms the center contact' 26 of the socket. The contact 26 extends beneath a yoke-shaped lug 27 carried by a plate 28 and makes Contact therewith except when forced back by the end of a lamp. The plate 28 is clamped beneath a conducting strip 29, which is secured in place by means of screws 30. The strip 29 is provided with a binding terminal 3l disposed opposite to the binding terminal 24 and adjacent the end of a groove 32 simin lar to the groove 25. As has been stated, the resilient contact 26 is so arranged that, when a lamp is not in position in the socket, it will make connection with the lower side of the lug 27, electrical connection thereby being established between the binding terminals 24 and 31. The result is that the socket is short-circuited whena lamp is not in position in the socket. The socket is intended to be connected in series with other sockets and, were this provision not made, the removal of one lamp would extinguish all the other lamps in the circuit.

Extending across the bottom of the chamof the plate 28 is a contact piece 33 the ends of which are bent up and over to form ears 34 and 35 by means of which the lamp receiver is secured to the base ll anc. 'which serve to establish connection between the lamp receiving shell and the binding terminal 31 through the intermediary or the plate 2S and strip 29. lll resilient tongue 3G is clamped between the strip 23 and the resilient contact 26, and is arranged to make connection with a corresponding contact on the lamp receiver for a purpose which will be hereinatterset forth.

rlhe lamp receiver comprises an insulating bushing 37 preferably formed of porcelain or the like and having secured to the upper rllhe ring l edge thereof a metallic ring 38. 33 is formed with upwardly extending projections 39 which enter corresponding slots 40 in the outwardly extending 'lange 4l of a threaded lamp receiving shell 42, the slots 40 being elongated in order to allow a slight rotative movement of the shell 42 relatively to the bushing 37. The `flange 4l is provided with notches and 4 of a shape corresponding to that or the ears 34 and 35 oit the contact piece 33 described above. When the lamp receiver is connected to the body, the ears and 35 enter the notches and 44 and can be made to engage beneath the i'lange il by imparting a rotative movement to the lamp receiver in a clockwise direcincase? Vmtionfwhereby a bayonet connection is established between the lamp receiver and the body with the lamp receiving shell in electrical connection, through the ears 34 and 35, contact piece 33, plate 28 and conducting strip 29 with the binding terminal 3l, and its center contact is in electrical connection, through the resilient contact 26 and strip 23, with the binding terminal 24.

It is desirable that the connection between the lamp receiver and body be a secure one and, to that end, I provide a catch 45 which is secured to the lower side oi' the flange 41 at a point somewhat to the left of the notch 43. The catch is secured by an eyelet and, in order to prevent lateral movement, is formed with a rearwardly extending tongue 46 which is bent up at its end to enter a corresponding slot formed in the flange 4l. The catch is bent downward and outward to form a shoulder 47 and a circumferentially extending portion 48 having .at its end a. downwardly in clined hook 49 which passes through an elongated slot 50 formed in the ring 38. The hook 49 enters a recess 51 cut out of the upper edge of the insulating bushing 37. l/Vhen the lamp receiving shell is in the position, relatively to the bushing 37, in which the projections 39 of the ring 38 are located n in the ends of the slots 40 adjacent the ber 2l and connected at its center to the end notches 43 and 44 the catch 45 'is in the position shown 1n Fig. 6, in which the hook 49 extends downwardly into the recess 51.

W hen the parts are in this position the ear 34 can enter the notch 43, upon" the lamp receiver being brought into the proper position relatively to the body. Upon a rotative movement in a clockwise direction being imparted to the lamp receiver, the ears 34 and 35 enter beneath the flange 4l and the ear 34 comes into engagement with the shoulder 47 oit the catch 45. A furifler rotative movement imparted to the lamp receiver has the eilect that the bushing 3T moves relatively to the lamp receiving shell, the latter being held stationary by reason of the engagement ot the car 34 to the shoulder if? et the catch. rEhe etl'ect ot such rotation of the bushing relatively to the lamp receiving shell is that the shoulder formed by vthe right hand corner of the recess 5l en 0tages the underside of the catch 45 and forces it into the position shown in Fig. S, in which the hook 49 closes the space 'between the 4l and the ring 2h and thereby prevents backward rotation of the bushing 37 except by the application of force. v

lll/*hen itis desired to separate the parts, this may be done by turning the bushing` 37 in a contra-clockwise direction, the olect of which is that the ear 34 engages the book 49 thereby preventing movement of the lamp receiving shell, and, the bushing 37 being forced to move relatively to the lamp receiving shell, the catch 45 is enabled to return to the position shown in Fig. 6. further rotativel movement of the bushing effects the turning of the lamp receiving shell also, so that the notch 43 comes into position above thek ear 34 and the notch 44 comes into position above the ear 35. The

llamp receiver may then be withdrawn by a straight pull.

The flange 41 of the lamp receiving shell is bent upward, at a point which will be opposite the spring tongue 36 when the lamp receiver is connected to the body, to form a table 53. Secured to the flange 41, is a spring contact finger 54, between which and the table 53maybe`placed an insulating film consisting of a thin disk 55 of mica or the like. The film 55 is suiiicient to insulate the finger 54 from the table 53 when, owing to the presence of a lamp in the socket, the difference of potential between these parts is not very great. In case of the destruction of the lamp however, the difference of p'otential between the finger 54 and the table 53 increases greatly with the result that the film 55 is punctured and the current finds its way from the finger-54 to the table 53, the socket being thereby short-circuited and the extinguishing of the other lamps in the socket being avoided. When the lamp is replaced the punctured film is replaced by a fresh one.

In use, the socket is connected in a high tension circuit in series with a number of other sockets or translating devices. When there is no lamp in the socket, current can pass through the same by way of the binding terminal 24, contact 26, plate 28, strip 29 and binding terminal 31. When, however, a lamp is inserted into the socket, the contact 26 is pressed inward until its end breaks contact with the lug 27 of the plate 28, the current then passing through the lamp and back to the binding terminal 3l by way of the Contact piece 33, plate 28 and strip 29. In case the lamp should burn out, or be accidentally broken, the insulating film 55 will become perforated and current will then flow. from the binding terminal 24 through the spring tongue 36, spring finger 54, flange 41, contact plece 33, plate 28 and strip 29, back to the binding terminal 31.' It will thus be seen that the binding terminals 24 and 31 will be in electrical connection regardless of whether the lamp be destroyed or no lamp be present in the socket, connection between the binding terminals is only made through the lamp. When the lamp contained in the socket has been destroyed, and the resistance film has consequently become perforated,|` it is only necessary to impart a slight turning movement to the bushf ing 37 whereupon the lamp receiver may be removed from the body. The film is then easily accessible and may be quickly replaced by a fresh one. The construction of the device so that the film is readily accessible for replacing is one of the important features of my invention since lamp sockets of this character are usually placed in positions which are difficult to reach.

While I havey described one embodiment of my invention, I.do not limit myself to that construction since changes may be made without exceeding the scope of my invention as expressed in the appended-claims. Moreover, some of the details of construction may be utilized in devices different from that described.

What I claim as new, and desire to secure by Letters Patent, is;

1. An electrical device comprising a member formed withk a bayonet`slot, a secondmember provided with a bay0net projection adapted to enter said slot upon one of the members being turned relatively to the other,

whereby a bayonet connection is established', an abutment adapted to be moved into the path of said bayonet projection to prevent withdrawal of the latter from the bayonet slot, and means, actuated on a further turning movement of one of the members relatively to the other, for eecting the movement of said abutment.

2. An electrical device comprising a member provided with a bayonet projection, a second member including two portions movable rotarily with respect to each other, said second-named member having a bayonet slot, an abutment carried by one of said members and movable into and out of closing position with respect to said" slot, and means, associated with the other portion, for operating said abutment when one of said portions is rotated with respect tothe other.

3. An electric lamp socket comprising a base carrying a center contact and a connector having a bayonet projection and a lamp receiver including an insulating member, a threaded contact member rotarily mounted on said insulating member and forming a bayonet slot between itself and said insulating member, an abutment carried by one of said members and movable into and out of closing position with respect to said slot, and means, associated with the other member, for operating said abutment when one of said portions is rotated with respect to the other.

4. An electric lamp socket comprising a base carrying a center contact and a connector having a bayonet projection, and a lamp receiver including an insulating member, a threaded contact member rotarily mounted on said insulating member and formin a bayonet slot between itself and said insu ating member, a resilient abutment carried by I 4: Loewe? one of said members and normal-1y located Vsubscribed my name in the presence of two Wtholt said slot, "che other mfember being Witnesses.

rovi 'ed with `a cam portion or engaging T gaid resilient abutment and moving it into REUBEN B' BENJAMIN said slot when one of said members is ro- Vitnesses: tated with respect'l to the other. CHARLES G. COPE,

In Witness whereof, I have hereunto MAEL REYNOLDS. 

